This invention relates to a semiconductor device, and more particularly to a semiconductor device which is allowed to function as a random access memory (RAM) cell or a photoelectro transducer.
The random access memory cells are customarily classified into two categories including the static type and the dynamic type. The former type is generally based on the concept of a flip-flop circuit and is inevitably involved with the drawbacks inherent to the flip-flop circuit. Namely, a fairly large area of a semiconductor chip is required for production of a memory cell, and more electric power is required to sustain information in a memory cell. The latter type is generally a combination of gate transistors and capacitors. Since the capacitors formed in semiconductor chips are more or less volatile, any of the dynamic type memory cells requires a refreshment circuit, albeit less electric power is required to sustain information. Further, the information memorized in a dynamic memory cell is destroyed when it is read out. In other words, the dynamic memory cells are involved with destructive read out.